Non-invasive thermal dispersion flow meter with fluid leak detection and geo-fencing control

ABSTRACT

A non-invasive thermal dispersion flow meter with chronometric monitor for fluid leak detection includes a heater, an ambient temperature sensor and a flow rate sensor which are configured to sense the temperature of a fluid in a conduit, and then monitor the flow of that fluid through the conduit. Based upon the ambient temperature sensor readings, the flow rate sensor and heater may be adjusted to optimize the operation of the system to detect leaks. Based on the sensor readings, the flow may be adjusted to prevent damage and leaks by relieving the system of excess pressure. Geographic location, occupancy sensors and occupant identifiers are used to control the system to facilitate operation and minimize leak damage when occupants are away.

RELATED APPLICATIONS

This Application is a Continuation in Part of, and claims the benefit ofpriority to, U.S. Utility patent application Ser. No. 15/396,346 filedDec. 30, 2016, entitled “Non-Invasive Thermal Dispersion Flow Meter WithFluid Leak Detection And Freeze Burst Prevention”, which is a Divisionalof, and claims the benefit of priority to, U.S. Utility patentapplication Ser. No. 13/899,450 filed May 21, 2013, entitled“Non-invasive Thermal Dispersion Row Meter with Chronometric Monitor forFluid Leak Detection and Freeze Burst Prevention”, and currently issuedas U.S. Pat. No. 9,759,632, which issued on Sep. 12, 2017, which in turnclaims benefit of priority to U.S. Utility patent application Ser. No.13/342,961 filed Jan. 3, 2012, entitled “Noninvasive Thermal DispersionFlow Meter with Chronometric Monitor for Fluid Leak Detection,” andcurrently issued as U.S. Pat. No. 9,146,172, which issued on Sep. 29,2015, which in turn claims benefit of priority to U.S. ProvisionalPatent Application Ser. No. 61/429,242 filed Jan. 3, 2011, entitled“Noninvasive Thermal Dispersion Flow Meter with Chronometric Monitor forFluid Leak Detection”, and also to U.S. Provisional Patent ApplicationSer. No. 61/542,793 filed on Oct. 3, 2011, entitled “Direct Pipe Clampon Flow Meter Leak Detector”.

FIELD OF INVENTION

The present invention relates generally to the field of fluid leakagedetection. More particularly, the present invention relates to devicesuseful for the monitoring and evaluation of fluid flow rates. Thepresent invention is more particularly, though not exclusively, usefulas a non-invasive leak detection system capable of detecting even thesmallest fluid leakage within a fluid conduit system, terminating fluidflow in response to the leak, and providing other indication, alert, andcontrol functions.

BACKGROUND OF THE INVENTION

In the process of residential or commercial building construction,builders will frequently pre-plumb water supply pipes, and then encasethe foundation level plumbing within a concrete mixture creating a floorslab. The plumbing will remain in use for the existence of the structureuntil it fails and leaks. Slab leaks typically start when a pinhole sizerupture forms in a pipe or fitting from a period of constant pressure,friction with the slab material, and thermal expansion and contraction.As more water passes through the opening, in time, the size of therupture increases. Undetected, the escaping water will eventually floodthe foundation, damage floors and walls and ultimately undermine theground beneath the structure due to erosion. The control of water haschallenged man since the beginning. The world today benefits and suffersfrom the conveyance and containment of this life giving fluid. No matterthe culture, the class, or the location, similar issues are considered,such as materials, installation, pressures, maintenance, effects ofinternal and external conditions, including water quality, climacticconditions, electrolysis, etc., Issues with any one of these may resultin undesirable effects and damages.

Leaks can be slow and gradual, taking years to detect until significantproperty damage occurs, or there can be large leaks that quickly producea variety of damaging results. Significant costs are expended everydayall over the world from these water-related damages. The costs are soextensive and pervasive, that nearly everyone in our modern world hasbeen personally affected.

Leaks occur at all phases of water system function, both during andafter construction. During construction leaks result from improperinstallation, faulty materials, testing, unintentional trade damage, andvandalism—to name a few. Once a water system is installed, formation ofleaks occurs due to corrosion, environmental effects, and impropermaintenance. An exemplary example of environmental effects causing leaksis during periods of extended below zero temperatures. When water isbelow its freezing point, the water turns from a liquid phase into asolid phase resulting in an increase of volume. An increase in volume ina closed system increases the system pressure causing strain andcompromising the structural integrity of the system, eventually causinga leak.

Costs are spread between responsible parties, insurance companies andoften to those not responsible who cannot prove otherwise, or becauseresponsible parties have no ability to pay the frequently large damages.Virtually anyone in the construction industry can tell you horrorstories about water damage during their most recent project. Most in theindustry accept these damages simply as part of the construction worldand never consider there may actually be a solution to eliminate orminimize these damages.

Once a building, home or facility becomes occupied, the risks of leaksmay shift, but still remain as a liability, as any insurance underwritercan attest. The repair and refurbishment resulting from leaks is anenormous industry, most recently exacerbated by the scares and realitiesof mold. Slow, hard to detect leaks within walls, ceilings or concealedareas often result in the most damage, as they introduce moisture into awarm, stable atmosphere of a controlled environment, resulting in moldgrowth that can cause extensive damage and may include condemnation ofthe home or building.

Large leaks or ruptures can be catastrophic within a very short amountof time, sometimes within minutes. In commercial structures, leaks candamage computer systems resulting in untold losses of computer data.These risks are not simply limited to property damage, but includepersonal injury and even death. Toxic mold has verifiably taken a numberof lives. Leaks also substantially increase the risk of electricalshock, not to mention medically sensitive risks caused by leaks. Leaksare indiscriminate of time, occurring when occupants are present oraway.

Until recently the prevention of leaks and/or mitigation of leak damageshave been very limited. The “Loss Prevention” programs of insurancecompanies have focused primarily on minimizing the underwriting ofclients with a history of previous leak claims rather than providing anytrue measure of “Loss Prevention”.

It is known that existing water meters are capable of detecting andreporting water consumption, but these systems, which employ paddlewheels, turbines, or other such impellers, suffer from mechanicallimitations which allow for small flow amounts to slip past the meterundetected and do not monitor water temperatures.

Another deficiency in currently available water monitoring systems isthe inability to easily and accurately determine whether occupants arepresent in the property. The inability to sense whether an occupant ispresent or away results in any leak being undetected for an extendedperiod of time until the occupant returns and the leak is discovered.

Manual on-off valves for water supply are ineffective for daily use dueto the lack of diligence on the property occupant that will notconsistently turn off a water supply, or doing so interferes with thenormal and expected water use in the occupant's absence. As a result, anautomated method for allowing an occupant to control water use duringperiods of absence or when a leak occurs will greatly increase theefficacy of leak detection and the minimization of water damage.

Additionally, in properties having multiple occupants in specific areas,such as an office building with multiple tenants or an apartmentbuilding with multiple residences, the inability to detect a leak in avacant unit can result in significant damage to both the vacant unit, aswell as the surrounding units when the water damage spreads throughoutthe building.

SUMMARY OF THE INVENTION

In a preferred embodiment of the present invention, the leak detectionsystem is a water flow monitor and alarm system for detecting waterleaking from the pressurized pipes or fixtures in residential andcommercial building structures. The sensor probes have no moving partsto wear out and can detect water flow as little as a few ounces of waterper hour. If water flows continuously for a preset time withoutstopping, it triggers an alarm. It may also trigger other functionsassociated with the system such as a display change and valve control.The alarm function can be set to alert the homeowner or a surveillancecompany monitoring the premises. Integrated into the system are userguides and features to aid the homeowner or a professional in detectinga leak.

Such an alarm condition could indicate a faulty valve or a more seriouscondition known as a “slab leak”. An undetected slab leak (a broken pipein or under a concrete slab floor) can cause extreme structural damagein excess of thousands of dollars, and render the property uninsurablefrom the resulting insurance claim.

In the preferred embodiment, two separate sensor probes are clampeddirectly onto the outside of a pipe or thermally conductive heattransfer medium between the fluid and the system to allow detection ofall flow conditions. Not just water loss under the hot water heater ordishwasher or an icemaker like other point of leak detection competitivedevices, but water loss for the entire structure. A comprehensive systemmay include moisture sensors together with the leak detection system.This will ensure both immediate and long-term protection of thestructure and its contents and detect leaks from the pressurized supplyside as well as the drain and waste systems, appliances, and waterintrusion from the outside environment. Resource conservation and watercost savings are also promoted by detecting unknown water loss longbefore thousands of gallons escape down the drain or into thestructure's foundation.

The preferred embodiment works by measuring the temperature at theupstream and downstream clamps. The downstream clamp contains both atemperature sensor and a heating element. The two temperature sensorsform part of the sensing portion of a Wheatstone Bridge where the amountof heat energy added by the heating element to keep the bridge circuitin balance is proportional to the flow rate of fluid in the pipe.

In an alternative embodiment, a single temperature sensor and a separateheating element are clamped onto a pipe. The heating element is locateda few inches downstream from the temperature sensor. The sensor and theheating element are both wrapped with insulation thereby isolating thesensor and heating element from ambient conditions and increasing theaccuracy of the measurements and the sensitivity of the system. Thisembodiment works by measuring temperature before the heater isenergized, then energizing the heater for a predetermined period oftime. The temperature is continuously monitored to determine the amountof time for the heat energy added by the heater to propagate to thetemperature sensor. That amount of time is used to determine the flowrate in the pipe. The longer the time for the heat energy to reach thesensor, the higher the flow rate is within the pipe. The shorter thetime for the heat energy to reach the sensor, the lower the flow rate iswithin the pipe. After the propagation time is determined, the heater isdeenergized to allow it and the sensor to return to ambient conditionsso a new test can be performed.

In an alternative embodiment, the addition of an external environmentsensor probe and temperature sensor package to a leak detection systemcreates a more comprehensive system able to prevent and detect leaks.The alternative embodiment works by taking the temperature at thetemperature sensor package of the leak detection system, the externalenvironment temperature sensor, and the additional temperature sensorpackage and feeding the data to a microprocessor where they are analyzedto determine whether the fluid is expanding by comparing the temperaturedata to the user inputted data stored in a control ROM and flash memory.If expansion is occurring, the microprocessor will open a relief valveand cause fluid to flow, releasing excess pressure and preventing damageto the structure's pipe system. In extreme conditions, themicroprocessor will shut off the isolation valve to prevent additionalfluid from entering the system and open a relief valve and cause fluidto flow, releasing excess pressure in the system. The microprocessorwill then open an air valve to aid the evacuation of the fluid in thesystem.

The control panel is easy to use and attractive. Its display providesreal-time system and flow status. The Panel will indicate an alarmcondition; the flow level when the alarm occurred, and sound a built-inbeeper, then if no action is taken it will activate an industrialquality motor-driven ball valve to shut off the water to the structure.The control panel will then display information to guide the homeownerthrough the process of detecting simple leaks such as a dripping faucet.The panel can also be used to select other operating modes or selectother features of the leak detection system such as monitoring the fluidtemperature and external environment temperature to prevent overpressureof the structure's pipe system

When the leak detection system is connected to an auto-dialer telephonedevice, it can alert anyone with a telephone that a problem exists. Whenconnected to an electric water valve, which is the design for theinitial product, it can shut-off the water automatically until thesystem is manually reset. Other devices may be connected to the leakdetection system to coordinate moisture and over-pressure sensors andleak detection throughout the entire structure.

In an alternative embodiment, the leak detection system includes aninterface for detecting the presence of an occupant at a particularproperty. Detection of an occupant can occur in a number of ways whichmay be implemented independently, or as a combined system. Occupantdetection includes geo-fencing detection using standard portableelectronics such as a cellular telephone having an application whichsenses the geographic location of an occupant, and compares thatlocation with a user-determined geographical range about the propertybeing controlled. When the occupant is within the user-determinedgeographical range, the system will operate as the occupant is present.On the other hand, when the geographic location of an occupant isoutside the user-determined geographical range, the system willautomatically switch to an AWAY mode, thereby providing a heightenedlevel of leak detection and interruption as preset by the occupant.

In addition to the portable electronics geographic location, the leakdetection system may incorporate alternative occupant detectors. Forinstance, the system may incorporate Radio Frequency Identification(RFID) tags coupled with RFID readers. In use, an occupant simply scansthe RFID tag when entering a property to activate the system in the HOMEmode. Similarly, when the occupant leaves the property, another scan ofthe RFID tag switches the system to the AWAY mode. Alternatively,multiple RFID readers may be placed throughout the property which,during the normal use of the property by the occupant, will sense theRFID tag presence and maintain the HOME mode. When the RFID tag is nolonger readable by any RFID reader within the property, the system willautomatically switch to AWAY mode.

Another alternative occupant detection system may include an optical orinfrared sensor which senses the physical presence of an occupant withinthe property. This sensor will simply alert the system of the presenceof a person within the property and enter the HOME mode of operation.

Yet another component which can assist in the determination of thepresence of an occupant is a temporary bypass timer which can bemanually set or triggered. This physical timer may have a fixed timeperiod such as a pushbutton that triggers a 30 minute timer, or may beadjustable such as a dial timer that can be set from 0 to 60 minutes.The timer will allow an occupant, such as a service person (housekeeper,gardener, service technician, etc.), to manually switch the system tothe HOME mode as needed, and the timer will automatically return to theAWAY mode with no further action needed. This process can be repeatedmultiple times if the timer period is insufficient for that particularoccupant, but absent an affirmative retriggering of the timer, thesystem will automatically return to the AWAY mode when the timerexpires.

BRIEF DESCRIPTION OF THE FIGURES

The novel features of this invention, as well as the invention itself,both as to its structure and its operation, will be best understood fromthe accompanying drawings, taken in conjunction with the accompanyingdescription, in which reference characters refer to similar parts, andin which:

FIG. 1 is an exemplary view of the controller of the present inventionas integrated with a structure, and showing the status panel of thesystem including an alarm indicator, an auxiliary indicator, a flowindicator, and a power indicator;

FIG. 2 contains three perspective views of the noninvasive sensors whenclamped onto a metal pipe;

FIG. 2A is a perspective view of the sensors and heater when clampedonto a plastic pipe through in-molding thermal carriers;

FIG. 3 is a basic electrical schematic diagram showing theimplementation of a Wheatstone bridge used to sense the energy requiredto balance the bridge, and to energize an LED when the detected flowrate is above an adjustable level;

FIG. 4 is a flow diagram of an exemplary operation of the system of thepresent invention, and includes a sequence of operation when employing amicroprocessor controller to monitor the trip level and timer settings;

FIG. 5 is a flow diagram of an exemplary operation of the system of thepresent invention, and includes a sequence of operation when employing amicroprocessor controller to cycle heater power to conserve energy andprevent excessive heating of the pipe section;

FIG. 6 is an electrical schematic showing the placement of thetemperature sensors on the pipe and amplifiers configured to detect theflow signal;

FIG. 7 is an exemplary operational flowchart showing the overalloperation of the system of the present invention;

FIG. 8 is a block diagram of an alternative embodiment of the presentinvention showing a user interface display receiving input fromtelephone, Internet, alarm system, geolocation system, manual overridecontroller, and point of leak detectors, coupled to an analog anddigital controller receiving input from dual temperature sensors and avalve for interrupting fluid flow through a conduit;

FIG. 9 is a block diagram of an alternative embodiment of the presentinvention showing a single sensor upstream from a heating element andhaving a central control unit with various inputs and outputs, alarm andmode control, and timer control. Additionally, the diagram illustratesthe interface between the central control unit, the temperature sensor,and the heater;

FIGS. 10A and 10B consist of a graph and its associated data pointsrespectively. The figures show temperature changes over time for noflow, low flow, and medium flow conditions in response to turning on theheater for a predetermined period of time when the ambient temperatureis approximately 75.degree. F.;

FIGS. 11A and 11B consist of a graph with its associated data pointswhich shows temperature changes over time for no flow, low flow, andmedium flow conditions in response to turning on the heater for apredetermined period of time when the ambient temperature isapproximately 37.degree. F.;

FIG. 12 is a diagram showing two temperature sensor packages attached toa fluid conduit system and an external environment temperature sensorconnected to a signal processor to form a circuit to detect changes influid temperature, fluid flow rate, and external environmenttemperatures;

FIG. 13 is a block diagram of an alternative embodiment of the presentinvention shown in FIG. 12 showing an external environment temperaturesensor and two temperature sensor packages coupled to analog and digitalcircuitry, a user interface display and three valves for controllingfluid flow;

FIG. 14 is a block diagram of an alternative embodiment of the presentinvention and includes a structure equipped with the present inventionsurrounded by an exemplary geo-fencing area, and depicts a number ofoccupant sensors such as RFID tags and readers, occupancy sensors,mobile electronics, and a GPS satellite and cellular communication towerwhich all cooperate to establish a location-based control of the systemto ensure proper HOME and AWAY mode settings;

FIG. 15 is an exemplary operational flow chart showing the operation ofthe present invention utilizing the geo-fencing and occupancy sensingdevices to control the HOME and AWAY mode settings to insure promptreaction to a detected leak; and

FIG. 16 is a block diagram of the present invention incorporating thegeo-fencing and occupancy detection system into a multi-unit property,such as an apartment, showing integration of the motion or infraredsensors, RFID tags and detectors, mobile electronics, and manual timer,which each controls an individual flow monitor and valve controller fora particular unit, and which can be independently operated apart fromthe remaining units providing a higher level of control than a singleproperty leak detector and controller system, and which can be furtherexpanded within a unit to provide appliance or fixture level detectionand fluid control.

DETAILED DESCRIPTION PREFERRED EMBODIMENT

This invention relates to an electronic thermal monitor system intendedto measure fluid flow within a conduit or pipe, by clamping directly tothe outside of a pipe or onto a thermally conductive heat transfermedium between the fluid and the system.

Referring to FIG. 1 , the present invention is suitable for applicationof leak detection technology into a structure 100 having a water inlet101, a water leak monitor 102, and a shut off valve 120. The water leakmonitor 102 includes a power indicator 104, a timer set 105 with anindicator 106, and a trip level set 108 with an indicator 110.Sensitivity adjustment 109 provides a user the ability to adjust thesensitivity of the device. A reset button 107 is provided to allow forthe system to be reset after an alarm condition has been generated.

In an exemplary embodiment, this invention is discussed in conjunctionwith a typical thin wall copper pipe section commonly found incommercial and residential plumbing systems that form the water supplyline. Since copper is an excellent conductor of temperature, this meterinfers the water temperature by measuring the outside skin temperatureof the pipe section. Another embodiment is to measure fluid flow withina confined conduit whereby the thermally conductive transfer medium isembedded within the conduit and allows for unimpeded and low heatmeasurements of fluids such as gasoline, diesel oil, liquid slurries, aswell as gases such as air or nitrogen.

The thermal conduction means in the exemplary embodiment are clampswhich mount to the pipe and form not only a mechanical connectionbetween the meter and the pipe, but a thermal connection as well. Theclamps are designed to transfer heat to and from the meter and the waterwithin the pipe. The pipe may be any shape to contain the fluid andallow a thermal conduction means to the fluid within.

In the exemplary embodiment there is one upstream temperature referenceclamp that contains an integrated temperature sensing element, such as athermistor, thermocouple, or resistance temperature detector (“RTD”),which reads the current temperature of the pipe and fluid within. Asecond sensor clamp, mounted downstream from the reference, alsocontains an integrated temperature sensing element and a resistiveheater which transfers heat energy into the pipe and the water within.This clamp performs the actual flow rate measurement.

Referring to FIG. 2 , the clamps are comprised of a heat sink mount or“shoe” 202 and 207 which partially wraps around the outside diameter ofthe copper pipe 200, and are retained by spring clips 203 and 206 tokeep them firmly pressed onto the pipe 200. The sensor/heat shoe 207 hasmounting holes for both the thermistor 205 and the heater 204. Thereference temperature shoe 202 has mounting holes for the referencethermistor 201. Since copper pipe 200 comes in various diameters, theshoes 202 and 207 may be configured in varying sizes and widthsdepending on the amount of surface area that is required to performeffective temperature coupling and heater loading.

While FIG. 2 depicts an exemplary embodiment of the electroniccomponents 201, 204, and 205 with unconnected leads, it should be notedthat either a single printed circuit board will be connected to theseleads or additional wires will be added to these leads to form a remotecontrol operation.

Additionally, FIG. 2A depicts a means to transfer heat through plasticpipe 225 by in-molding thermal carriers 226 and 227 and mounting thethermistors 201 and 205 and heater 204 directly to these thermalcarriers 226 and 227. This method allows this invention to operate usingnon-thermally conductive materials such as plastic, Teflon, ABS, PVC,etc.

Referring to FIG. 3 , as the heater R17 increases in temperature, thethermally coupled thermistor R11 senses the temperature change andadjusts the servo amp U1A to maintain the equilibrium of the WheatstoneBridge circuit by modulating the power transistor Q1, The powertransistor Q1 will either add or subtract power to the heater R17 tomaintain the Wheatstone Bridge in balance. This system forms a closedloop feedback when the servo amp U1A reads the reference temperaturethermistor R10, adds in the sensitivity bias voltage U1D, and thencompares it to the current flow R11 temperature. This operation allowsthe reference thermistor R10 to adjust the circuit for any changes inincoming water temperature and allows the heater R17 to provide aconstant temperature above the incoming water main as set by thesensitivity adjustment R5. Greater water flows require more heat tomaintain this temperature difference and it is the amount of powerconsumed by the heater, to balance the bridge, which is read by thecomparator U1C, to establish a flow trip threshold which is adjustablevia resistor R1. If heater power increases above the preset tripthreshold, the comparator U1C will activate and glow the TRIP LED D2which, in other embodiments, may also be connected to a micro-controllerto monitor flow and time.

FIG. 4 is a flowchart that describes an embodiment with a sequence ofoperations when employing a microprocessor controller to monitor thetrip level and timer settings. When the trip level is exceeded, acounter is continuously incremented until it matches the timeout settingat which time the alarm output is activated. In this example, the alarmwill automatically cancel once the trip value falls below the tripthreshold, however some installations require latching the alarm on whentripped so it will remain active after the flow has been shut-off byemploying an electric water shut-off valve 120 (not shown). The alarmoutput can be hard wired to existing commercial alarm panels. The alarmoutput signal may also drive a low power RF transmitter and pass itsstatus via wireless signal.

Referring to FIG. 5 , the micro-controller may also be configured tocycle heater power to conserve energy and prevent excessive heating ofthe copper pipe section. Detection of the leak will still occur when theunit powers up and performs its leak tests over time. After the systemwakes up and applies power to the heaters, the system will go intonormal operation.

FIG. 6 is an electrical schematic showing the placement of the flowsensor 610 clamped to a water pipe (conduit) 611, and amplifiers 614 and616 configured to form a circuit to detect the variations in theresistance of the flow sensor 610 produced by the flow of fluid 625through the conduit 211. The amplifiers 614 and 616 feed their signalsinto Analog to Digital Converters 619 and 620 to create a digitalrepresentation of the flow signals. The digital representations are thenfed to a microprocessor 621 where they are analyzed to determine theflow rate by comparing the flow data to the data stored in the controlROM and flash memory 622. The microprocessor 621 will then performvarious functions 624, such as energize a relay, illuminate an LED, orcreate an audible alarm, based on the measured flow rate as compared tothe data stored in memory 622. The microprocessor 621 will also sensethe amount of current flow through the flow sensor 610 and adjust it asnecessary to maintain a constant electrical current through the flowsensor 610.

FIG. 7 is an exemplary operational flowchart showing the overalloperation of the system of the present invention and is generallyreferred to as item 250. At the start of the operation 252, the sensoris deenergized to allow it to cool to ambient temperature and establisha baseline temperature for use in future calculations 254. The sensor isthen heated to a reference temperature plus an offset temperature 256.If the temperature has not been calibrated 258, then the system willreset the accumulator and alarms 260 and to check to see if the flowtimer has expired 262. If the flow timer has expired 262, the systemwill reset the flow timer 264 then restart the process 254. If the flowtimer has not expired 262, the system will go to step 256 to heat thesensor 256.

If the temperature has been calibrated 258, then the system will checkfor the presence of a time delay 266. If the delay time value has notbeen reached, the system will return to step 256 to continue heating theRTD. If the delay time value has been reached 266, the system will addtime to the accumulator and record flow 268. If the accumulator has notreached its maximum value 270, the system will return to step 256 whereit will continue to heat the RTD. If the accumulator has reached itsmaximum value 270, the system will compare the calculated flow to theflow trip point 272. If the trip point has not been reached 272, thesystem will return to step 268 where it will add time to the accumulatorand record flow. If the trip point has been reached 272, the system willactivate functions such as an alarm, an indicator, and automatic valveclosure 274. It should be appreciated by someone skilled in the art thatmany different functions may be controlled by the system and thefunctions listed above are not the exclusive functions of the system.

FIG. 8 is a diagram of an alternative embodiment of the presentinvention and is generally designated 300. This diagram shows a clamp ontemperature sensor package 306 which includes dual temperature sensors324 and 326 separated by a known distance 328. The temperature sensorpackage 306 is coupled to a controller 302 having both analog 318 anddigital 312 circuitry, and equipped with a user interface display 304and a valve 308 for interrupting the flow of water through a pipe orconduit 310 should a leak be detected. The controller 302 has aninternal power supply 321, a microprocessor 314 with memory 316, andinterface circuits to control such things as the isolation valve 308,temperature sensor package 306, and the display unit 304. The display304 utilizes a microcontroller 331 to control the user display panel330, and external interfaces 332 such as telephone, internet, and alarm.

The present invention as shown in FIG. 8 also includes an interface fordetecting the presence of an occupant at a particular property.Detection of an occupant can occur in a number of ways which may beimplemented independently, or as a combined system. These inputs caninclude a geolocation system, a manual override controller (manualtimer), point of leak detectors, and occupant detectors.

Specifically, one aspect of occupant detection includes geo-fencingdetection using standard portable electronics such as a cellulartelephone having an application which senses the geographic location ofan occupant, and compares that location with a user-determinedgeographical range about the property being controlled. When theoccupant is within the user-determined geographical range, the systemwill operate as the occupant is present. On the other hand, when thegeographic location of an occupant is outside the user-determinedgeographical range, the system will automatically switch to an AWAYmode, thereby providing a heightened level of leak detection andinterruption as preset by the occupant.

In use, customers of system 900 (shown in FIG. 14 ) may use their leakdetection system mobile application-equipped cell phone to notify theserver of system 900 when a virtual GPS geo-fencing boundary has beenentered or exited.

If enabled, the server would then perform an automatic action thatselects the appropriate HOME/AWAY selection according to GPS data passedon to the server, from the occupant's cell phone device.

In this configuration, the application would be running as a backgroundtask reading the GPS location service of the cell phone every fewminutes. The occupant can set localization GPS coordinates of the leakdetection system 900 and then pass those values on to the host databaseand system 900. An algorithm reads the localized GPS data and forms avirtual perimeter around those coordinates which are also saved withthat occupant's data; this has been referred herein as the “geo-fencingboundary.” The occupant's mobile application's background task routinelysends identification and present GPS values. The database runs a servicethat compares the present GPS data to the geo-fencing boundary perimetercoordinates, and determines an inclusive or exclusive relationship ofthe virtual boundary; the occupant is either within the boundary oroutside the boundary.

Home Mode would be transmitted to the leak detection system 900 if thefollowing conditions exist:

1—This function is activated and enabled;

2—The GPS data is available;

3—The cell phone can make internet connectivity;

4—The system can identify the occupant's system 900;

5—The system 900 must have previously stored its GPS local data;

6—The database determines an inclusive relationship within the virtualboundary;

7—According to the running database, the HOME mode must not already beselected; and

8—Any other registered occupant is already recorded to be within thevirtual boundary.

Similarly Away Mode would be transmitted to the leak detection system900 if the following conditions exist:

1—This function is activated and enabled;

2—The GPS data is available;

3—The cell phone can make internet connectivity;

4—The system can identify the occupant's LDS system;

5—The system 900 must have previously stored its GPS local data;

6—The database determines an exclusive relationship outside the virtualboundary;

7—According to the running database, the AWAY mode must not already beselected; and

8—All registered occupants are outside of the virtual boundary.

In addition to the portable electronics geographic location, the leakdetection system may incorporate alternative occupant detectors. Forinstance, the system may incorporate Radio Frequency Identification(RFID) tags coupled with RFID readers. In use, an occupant simply scansthe RFID tag when entering a property to activate the system in the HOMEmode. Similarly, when the occupant leaves the property, another scan ofthe RFID tag switches the system to the AWAY mode. Alternatively,multiple RFID readers may be placed throughout the property which,during the normal use of the property by the occupant, will sense theRFID tag presence and maintain the HOME mode. When the RFID tag is nolonger readable by any RFID reader within the property, the system willautomatically switch to AWAY mode.

Another alternative occupant detection system input into the display 304may include an optical or infrared sensor which senses the physicalpresence of an occupant within the property. This sensor will simplyalert the system of the presence of a person within the property andenter the HOME mode of operation.

Yet another input into the display 304 which can assist in thedetermination of the presence of an occupant is a temporary bypass timerwhich can be manually set or triggered. This physical timer may have afixed time period such as a pushbutton that triggers a 30 minute timer,or may be adjustable such as a dial timer that can be set from 0 to 60minutes. The timer will allow an occupant, such as a service person(housekeeper, gardener, service technician, etc.), to manually switchthe system to the HOME mode as needed, and the timer will automaticallyreturn to the AWAY mode with no further action needed. This process canbe repeated multiple times of the timer period is insufficient for thatparticular occupant, but absent an affirmative retriggering of thetimer, the system will automatically return to the AWAY mode when thetimer expires. a geolocation system input to display 304. Additionally,a manual override controller such as a manually activated timer devicemay be incorporated to provide a manual temporary bypass feature toplace the system in the HOME mode.

An Alternative Embodiment

Now referring to FIG. 9 , an alternative embodiment of the presentinvention is shown and is generally designated 500. This embodimentconsists of one temperature sensor 520, such as a RTD, thermistor, orthermocouple, clamped onto a pipe or conduit 524 and a heating element518 mounted a distance 522 downstream from the temperature sensor 520.The temperature sensor 520 and heating element 518 are both wrapped orcovered with an insulation material 516 thereby increasing the accuracyand sensitivity of the system.

This alternative embodiment uses heat conduction, propagation, and timeto determine if there is liquid flow within an enclosed metallic conduit524. FIGS. 10A, 10B, 11A and 11B consist of graphs and the associateddata points of temperature response to a known amount of heat energyadded to a conduit having a no flow, low flow, and medium flowcondition. The graphs and data points are for a warm test and cold testrespectively. Two elements are required to electrically perform thisfunction. One is a temperature sensor 520, either analog or digital, andthe other is a resistive heater band 518 which wraps around the outsidediameter of the conduit 524. It should be noted that the heater 518 andsensor 520 are separated by a short distance 522, such as 1″ to 3″, inorder to create more average heating across the conduit 524 crosssection, and also allow the internal flowing liquid 534 to carry awaythe conducted heat via convection cooling of the conduit 524 itself.

In normal operation, this embodiment works in an intermittent operation.After a calibrated tune has elapsed, the heater 518 becomes energized,which forces heat energy into the conduit 524. The controller 502 wouldread the temperature sensor 520 just prior to heater 518 activation, andstored that value for further calculations. Conducted heat from themetallic conduit 524 will readily propagate from the center of the heatsource 518 and outward eventually reaching the temperature sensor 522.The amount of time it takes for the heat to propagate to the temperaturesensor 520 is recorded in the controller 502 and is a direct function ofthe liquid flow 534 within the conduit 524. Long propagation timesreflect large effective flow rates.

The heater power is removed after a predetermined “no-flow” conditiontimer expires. The controller 502 will continue to read the temperaturesensor 520 to continually analyze the heat propagation and lock onto avalue that represents the peak temperature attained. This value is alsoa direct function of the liquid flow 534 within the conduit 524. Higherpeak temperatures represent low effective flow rates, as the heater 518is simply creating a no flow “pocket” of liquid, with little to noconvective forces to carry away the applied heat energy.

Finally, after a predetermined amount of time has elapsed, thecontroller 502 acquires one final reading from the temperature sensor520 and compares it to the previously saved value before the heater 518was activated. The ratio of the before and after temperature readings isalso a direct function of the liquid flow 534 within the conduit 524.The closer the two values are, the greater the effective flow rate iswithin the conduit 524 as the flowing liquid 534 is restoring theambient fluid temperature to nullify the effects of the previously addedheat energy.

All of the calculated temperature and time variables are scored withinan algorithm that normalizes the effective flow rate with respect toambient temperature and conduit/heater 524/518 thermal conductivity. Thecalculated score determines the liquid flow 534 rate, then thecontroller 502 records that rate, powers down for a short period of timeas determined by the Master Time value 526, and allows the heater 518and temperature sensor 520 to return to ambient conditions throughnatural convection.

As the system continues to move through heating and cooling cycles, therunning status is accumulated. If the flow rate over all the cycles hasnot provided a single “no-flow” score, the system will enter an alarmstate where it will either activate a relay 514, create an audible alert512, or do both. The alarm may be cancelled by stopping the fluid flowor by switching to another mode of operation 510, either HOME or AWAY,which effectively resets all timers and scoring status results.

The heater 518 and temperature sensor 520 must be properly affixed tothe conduit 524 to ensure consistent results over a long period of timemeasured in years. The heater 518 is a flexible silicone band which canwrap around the conduit 524 and be held in place with a self-adhesivevulcanizing wrapping tape specifically designed to seal out moisture andprovide continuous pressure on the heater 518 ensuring optimal thermalconductivity over time. It is to be appreciated by someone skilled inthe art that many heater 518 designs exist that will satisfy therequirements of the system. The temperature sensor 520 also requires thesame treatment during installation to ensure that the conduit 524temperature is properly reported. It is also imperative that the entireheater/sensor 518/520 section, and a few inches beyond, be enclosed inthermal insulation 516. This prevents ambient or environmental aircurrents from affecting the calibrated flow readings by heating orcooling effects that are not the direct result of the fluid flow 534within the conduit 524.

Intermittent operation of the heater 518 is required to provide theextended “no-flow” time period with an opportunity equilibrate withambient conditions. Otherwise, the heater 518 and temperature sensor 520would create a localized “hot water heater” within the test section ofthe conduit 524. Therefore, this device may not be used to measure flowrate or flow total as do other technologies, such as Thermal Mass FlowMeters. While this system is currently described to operate through aclosed section of copper tubing/pipe 524, it may also operate throughplastic conduit provided that the test section has in-molded metalplates or “shoes” within. The heater 518 and temperature sensor 520requires direct thermal conduction of the fluid within in order toperform the same operation of an all-metal design.

An AC/DC power supply 504 may be used since the heater 518 requiressignificant energy output (>12 Watts) to perform its tests accuratelyand reliably. Alarm panel interfacing may also be expanded to includeboth wired and/or wireless operation for command/control facilities.

Installation and Calibration

This alternative embodiment of the present invention requires about8″-10″ of clean copper pipe 524 to properly assemble the test section.The section of water pipe 524 selected should pass all incoming supplyto the entire structure and should not be located outside whereprotecting the heater 518 and temperature sensor 520 elements would beimpossible,

Once the heater 518 and temperature sensor 520 have been properlyinstalled and the wiring and power have been completed, the device mustbe calibrated to the particular installation. Before activating thecalibration function, all water flow in the test section must be halted.

The calibration function can be activated by an on-board switch, orwireless command, or a unique mode selection. During calibration, theunit will activate the heater 518. When the temperature sensor 520records a temperature increase of 4.degree. F.-10.degree. F., the timewhich passes during this test is recorded by the controller 502 andstored for all future heater timing variables. Calibration finishesautomatically and the system will be able to alert the installer ifthere is a problem or start performing normal operations if all is well.

This invention is a fluid flow meter with many applications andembodiments incorporating a unique method of flow measurement utilizingnoninvasive thermal anemometry. The use of a Wheatstone Bridge greatlyincreases the system sensitivity and accuracy allowing it to be used inmany applications.

Freeze Burst Detection and Prevention

FIG. 12 is a diagram of an alternative embodiment of the presentinvention and is generally designated 700. The diagram shows a primarytemperature sensor package 702, attached near the inlet of a fluidconduit system 720, secondary temperature sensor package 706 attached tothe fluid conduit 720 near the termination point, and an externalenvironment temperature sensor 704, all connected to a signal processor710 to form a circuit to detect variations in the resistance of thesensors. The resistance measurements of the temperature sensor packages702 and 706 can be used to determine fluid temperature and fluid flowrate simultaneously. It is appreciated by those skilled in the art thatalternative temperature sensor packages 702 and 706 may be usedutilizing alternative temperature sensing elements such as a thermistor,thermocouple, or resistance temperature detector. The resistancemeasurements are fed into the signal processor 710 then converted intodigital signals representing flow and temperature of the fluid in theconduit. The digital signals are then fed to a microprocessor 712 wherethey are analyzed to determine the flow rate by comparing the flow datato the data stored in the control ROM and flash memory 716, thetemperature by comparing the temperature data to the data stored in thecontrol ROM and flash memory 716, and the temperature difference betweenthe conduit system's 720 inlet and outlet fluid temperatures bycomparing the temperature data of temperature sensor packages 702 and706.

The external environment temperature sensor 704 detects temperaturechanges in the external, or ambient, environment. The sensor 704 feedsthe resistance measurements to the signal processor 710 to create adigital signal of the temperature data which is fed to a microprocessor712 where it is analyzed to determine the temperature by comparing thetemperature data to the data stored in the control ROM and flash memory716.

The flow and temperature data from the sensors are further analyzed bythe microprocessor 712 to determine the state of the fluid by comparingthe flow and temperature data of the sensors to the user-inputted datastored in the control ROM and flash memory 716. The microprocessor 712will perform various functions 714, such as open a valve, energize arelay, illuminate an LED, or create an audible alarm, when the measuredflow and temperature data triggers a response based on the user datastored in memory 716.

The diagram shows an isolation valve 722 for interrupting fluid flowinto the conduit system 720, a relief valve 724 for releasing the flowof fluid in the system through a drainage pipe 726, and an air valve 728to allow atmospheric air to enter into the system. Air valve 728 islocated at a high point in the system and relief valve 724 is located ata low point near the end of the system, The microprocessor 712 will openrelief valve 724 when a value stored in control ROM or flash memory 716is reached by the sensors 702, 704, and/or 706, For example, at 32degrees Fahrenheit water freezes and expands, increasing its volume.Therefore if the fluid is water and the temperature is at 32 degreesFahrenheit a determination that the water is expanding will be made andthe relief valve 724 will be opened. If the value is at or below asecondary value stored in control ROM or flash memory 716, such assevere freezing conditions for water, microprocessor 712 will closeisolation valve 722 to prevent water from entering the system and openrelief valve 724 to evacuate the water in the system. The air valve 726is then opened to allow atmospheric air to enter the system to aid theevacuation of fluid and prevent the formation of a vacuum. The valveswill be installed in locations to allow the most efficient fluid flowthrough the system. The control ROM and flash memory 716 can storeseveral values for different trigger points such as the temperaturedifference between inlet and outlet fluid temperatures.

FIG. 13 is a diagram of an alternative embodiment of the presentinvention shown in FIG. 12 and is generally designated 800. This diagramshows primary clamp on temperature sensor package 806 which includesdual temperature sensors 824 and 826 separated by a known distance,secondary temperature sensor package 840 which includes dual temperaturesensors 842 and 844 separated by a known distance, and an externalenvironment temperature sensor 827. The primary temperature sensorpackage 806, secondary temperature sensor package 840, and externalenvironment temperature sensor 827 is coupled to a controller 802 havingboth analog 818 and digital 812 circuitry, and equipped with a userinterface display 804 and an isolation valve 808 for interrupting theflow of water through a pipe or conduit system 810 should a leak bedetected, a relief valve 809 for releasing the flow of water in a pipeor conduit system 810 through a drainage pipe 807 should excess pressurebe detected, and an air valve 846 to open the system to the atmosphere.Isolation valve 808 is installed near the inlet of the conduit system810, air valve 846 is installed at a high point in the system, andrelief valve 809 is at a low point near the end of the system. Thelocation of the valves will allow the most efficient fluid flow throughthe system.

The controller 802 has an internal power supply 821, a microprocessor814 with memory 816, and interface circuits to control such things asthe isolation valve 808, relief valve 809, air valve 846, primarytemperature sensor package 806, secondary temperature sensor package840, external environment temperature sensor 827, and the display unit804. The display unit 804 utilizes a microcontroller 831 to control theuser display panel 830, and external interfaces 832 such as telephone,internet, and alarm.

Another Alternative Embodiment for Geo-Fencing Control

Referring now to FIG. 14 , a block diagram of an alternative embodimentof the present invention is shown and generally designated 900. System900 includes a structure 902 equipped with the present invention 904surrounded by an exemplary geo-fencing area 914 and having a water lineinput 906 with a fluid flow monitor and valve 908 as previouslydescribed herein. Downstream from fluid flow monitor and valve 908 isproperty supply line 910 which provides water supply to the structure902 and the appliance and fixtures therein. It is contemplated that thefluid flow monitor and valve 908 may be integrated into a single unitfor ease of installation without departing from the spirit and scope ofthe invention. The integrated fluid flow monitor and valve 908incorporates the fluid flow monitors as previously described herein. Itis also contemplated that the fluid flow monitor and valve 908 may beinstalled inline in existing conduits by cutting a portion of theexisting water line and installing the fluid flow monitor and valve 908in place of the removed portion of the existing water line.

System 904 may be equipped with an antenna 912 which provides wirelesscommunication to other components within the system 900, or to systemsor services outside the specific system of the present invention, suchas outside service providers (fire, county water services, alarmcompanies, etc.). Wireless communication may be accomplished using anywireless communication technique or protocol known in the art.

System 900 includes a location based area 914 which is often referred toas a geographical location area, geo-fencing boundary, or geo-fencingarea, that determines a range within which the system may be operated orthe presence of an occupant may be sensed. For instance, in a preferredembodiment of the present invention, geo-fencing area 914 may have anouter limit one mile from the structure 902 such that the system canswitch from AWAY mode to HOME mode when the occupant approaches. Inother circumstances, the system may be set such that the geo-fencingarea 914 outer limit is minimal, such as when an occupant enters thestructure 902 or comes within 100 feet to ensure that there is onlyminimal time elapsing between the system switching to the HOME mode andthe occupant actually entering the property 902.

In this embodiment, a personal electronic device 916A, such as acellular telephone or other portable electronic device, receives aGlobal Positioning Satellite (GPS) signal from a GPS Satellite 920 fromwhich the device can determine its location. This GPS location fordevice 916 is then compared to the geo-fencing boundary 914 and it isdetermined whether the device 916 is within the geo-fencing boundary,indicating whether the occupant with the device 916 is within theboundary 914. If the occupant is within the boundary, the system entersthe HOME mode, and if not, the system will remain in the AWAY mode.

As shown in FIG. 14 , there are a number of portable electronic devices916, including 916A and 916B which are both within the geo-fencingboundary 914 which would trigger the system to enter the HOME mode. Onthe other hand, portable electronic devices 916C and 916D are outsidethe geo-fencing boundary 914 and which would not trigger the system tothe HOME mode. In this embodiment, as long as at least one portableelectronic device 916 is present within the boundary 914, the systemwill be in the HOME mode.

As shown in FIG. 14 , system 900 includes a cellular telephonecommunication system 918 which is known in the art, and provides awireless communication link between devices 916 and system 904, andwhich may include a traditional wireless telephone connection, or mayutilize a wireless data connection, such as through cloud 930 to a host932, and further through cloud connection 936, such as an Internetconnection.

Also shown in FIG. 14 , system 900 includes a number of occupantsensors, such as RFID tags 922 and RFID readers 924. In thisapplication, RFID tags 922 are provided to occupants of structure 902.As the occupant approaches structure 902, the RFID tag is passed near anRFID reader 924 to signal that the occupant is returning to theproperty. For instance, occupant with RFID tag 922A, when entering theproperty, passes its RFID tag across a conveniently placed RFID reader924 (such as by the door), which signals the system 900 to enter theHOME mode. In this example, RFID tag 922 is within the geo-fencingboundary 914 and thus may be within range for RFID reader 924 to sensethe presence of the occupant, thus entering the HOME mode. However, asshown in FIG. 14 , RFID tags 922C and 922D are both outside thegeo-fencing boundary 914 and do not cause system 900 to enter the HOMEmode. As long as at least one RFID tag is within range of an RFID reader924, the system 900 is in the HOME mode.

In a preferred embodiment, property 902 may be equipped with additionalRFID readers, such as RFID reader 924A. This allows for the distributedsensing of the presence of an RFID tag 922 within the geo-fencingboundary 914. Using this approach, an occupant need not specificallypresent the RFID tag 922 to a RFID reader 924; instead, the multipleRFID readers 924, 924A, etc. can sense the presence of the RFID tag 922anywhere within the geo-fencing boundary maintaining the system in theHOME mode. When an RFID tag is no longer sensed within the geo-fencingboundary 914, the system will switch to the AWAY mode until an RFID tagis again detected within the boundary 914.

The system 900 shown in FIG. 14 , as previously shown in FIG. 8 , alsoincludes an interface for detecting the presence of an occupant at aparticular property. Occupant sensors 934 detect the presence of anoccupant through motion or infrared technology. The optical motionsensor technology and infrared technology contemplated herein is anytechnology known in the art and capable of detecting the presence of anoccupant without any action by the occupant. The system receives inputfrom one or more occupancy sensors 934 and if an occupant is detected,places the system into the HOME mode until occupancy is no longerdetected. This allows for the simple and routine detection of anoccupant without any special action being required by the occupant toplace the system 900 in a HOME or AWAY mode, thus enhancing theusefulness of the system by removing the possible user-error from theoperation of the system.

An additional occupancy sensor used in the present invention 900 whichcan assist in the determination of the presence of an occupant is atemporary bypass timer 935 which can be manually set or triggered. Thisphysical timer may have a fixed time period such as a pushbutton thattriggers a 30 minute timer, or may be adjustable such as a dial timerthat can be set from 0 to 60 minutes. The timer will allow an occupant,such as a service person (housekeeper, gardener, service technician,etc.), to manually switch the system to the HOME mode as needed, and thetimer will automatically return to the AWAY mode with no further actionneeded. This process can be repeated multiple times of the timer periodis insufficient for that particular occupant, but absent an affirmativeretriggering of the timer, the system will automatically return to theAWAY mode when the timer expires. Additionally, a manual overridecontroller such as a manually activated timer device may be incorporatedto provide a manual temporary bypass feature to place the system in theHOME mode.

In addition to occupant-based detection, system 900 also includespoint-of-leak detectors 933. In use, point-of-leak detectors are placedadjacent water-using appliances or fixtures, and detect the presence ofwater, such as when a laundry supply hose bursts, a toilet tank cracks,or other leak events. The input from these detectors 933 are provided todisplay 304 and utilized to control the valves and associated flow ofwater to the leak.

Referring now to FIG. 15 , an exemplary operational flow chart showingthe operation of the present invention utilizing the geo-fencing andoccupancy sensing devices to control the HOME and AWAY mode settings toinsure prompt reaction to a detected leak is shown and generallydesignated 1000.

Flow chart 1000 begins in step 1002 and proceeds to the configuration ofmembers in step 1004. Specifically, the members that are configured tocommunicate with a specific system 900 are identified using a portableelectronic device 916 (e. g. cellular telephone), or RFID tag 922. Next,the geo-fencing range, or geographical boundary 914, is determined forsystem 900. This range can be user-determined, and may vary based on thetype of property incorporating system 900.

Once each member is configured in step 1004, the location of each memberis determined in step 1008. As outlined above, this locationdetermination may be made using GPS data, RFID data, or a combination ofsuch data.

At this point in the flow chart 1000, the location of each member isdetermined in step 1004, and the geo-fence range has been determined instep 1006. In step 1010, it is determined whether there is any memberwithin the range of the geo-fencing boundary. If no member wasdetermined to be in range in step 1010, step 1011 determines whether aperson was detected within the geo-fencing boundary 914, or within theproperty 902 depending on how the system 900 is configured.

If no person is detected an integrating timer is incremented in step1024 to avoid false AWAY mode setting by system 900. Specifically, adelay timer is used in flow chart 1000 to require the absence of anoccupant for a set period of time before the system switches to an AWAYmode in order to provide for brief instances where the system 900 doesnot sense the person even though the person has not left the premises,such as if the person entered a closet, bathroom, or was brieflyout-of-range of the occupant sensor. If the time delay is not at itsmaximum, the delay count is increased in step 1026, and the operationreturns along path 1028 to continue to check for the presence of membersor occupants.

This process repeats until a member is in range in step 1010, a personis detected in step 1011, or the maximum count has been reached asdetermined in step 1024. If no member is present, no person is detected,and the timer expires, the system 900 enters the AWAY mode in step 1030.If, on the other hand, a member is in range in step 1010, or a person isdetected in step 1011, data path 1012 leads to step 1014 where thesystem is placed in the HOME mode.

Flow chart 1000 steps 1014 and 1030 both lead to the step 1016 where itis determined whether a flow trip point has been reached. This trippoint, as described herein, is user-determined and can be set to variouslimits throughout the day and week to accommodate scheduled activity andconsumptions, such setting higher flow limits during periods of laundry,showers, dishwashing, or garden watering, and at lower flow limitsduring periods of absence, such as working hours or overnight duringsleeping hours. If no flow trip point is reached in step 1016, controlreturns along line 1018 to the main control path and step 1008. On theother hand, if the flow trip point has been reached in step 1016, thesystem checks to determine whether the manual temporary bypass has beenset in step 1020. If the manual temporary bypass has not been set, thesystem activates flow lock in step 1022, may notify alarms or otherresponses based on the configuration of system 900, and ends in step1024. If the temporary bypass has been set as determined in step 1020,the system returns along path 1018 to step 1008 and resumes as describedabove.

Referring now to FIG. 16 , a block diagram of the present inventionincorporating the geo-fencing and occupancy detection system 900 into amulti-unit property, such as an apartment, is shown and generallydesignated 950. Property 952, in this embodiment, is representative of amulti-unit property, such as an apartment or multi-unit industrialproperty. In this embodiment, the particular use of such property 952 isnot limiting, rather, any property having multiple water destinations isfully contemplated herein. The present invention contemplates that theproperty may be large in nature with multiple separate living units, ora single property having multiple water destinations (appliances andfixtures).

System 950 includes units 900A, 900B, 900C, 900D, 900E, and 900F. Eachof these units may be a system 900 of the present invention as describedabove, or a system having a combination or one or more features andcomponents of system 900. While each unit 900A-F are shown to beduplicates, it is to be appreciated that the configuration of each unitmay differ, and no limitations on the applicability of the presentinvention to various configurations is intended.

Referring to unit 900A, an optical motion and infrared sensor 934 iscombined with an RFID tag 922A and corresponding sensor 924. Also, unit950A is provided with a manual timer 936. As described above, theoptical motion and infrared sensor 934, RFID tag and sensor 922A and924, and timer 936 provide a unit-specific measure of security andoperation of system 900. Also provided is a personal electronic device916A which corresponds to unit 950A such that when the device 916A iswithin the geo-fencing boundary (not shown this figure), the system 900activates to place the system in the HOME mode. Similarly, when personalelectronic device 916F leaves the property 952 and no other occupant isdetected, the system 900F enters the AWAY mode.

In the event that the system 900 detects a leak or an over-flowcondition using flow meter and valve combination 908A, the water flowingfrom main supply line 954 through branch line 956 can be interruptedusing the valve within 908A. In such circumstance, the flow of water tothe other unites 900B-F will not be interrupted, with only the water tounit 900A bring interrupted due to the over flow condition. It is to beappreciated that using the same system 900, each of the units 900B-F canbe monitored and protected from water damage using the same method andsystem configuration.

As used herein, RFID tags 922 are identified to communicate with aspecific RFID reader 924. As is known in the field of RFID accesscontrol, a single RFID tag may be configured to be accepted by more thanone RFID reader. For instance, a building maintenance technician mayhave an RFID tag that is configured to access all RFID readers inproperty 952, whereas a specific tenant of a single unit will have anRFID tag that is configured to access only that tenant's unit RFIDreader.

The system 900 of the present invention can also sense, in a particularconfiguration, excessive flow to more than one unit, such as the flowthrough branch line 956 to units 900A, 900C, and 900E. In the event thatflow through branch 956 exceeds a predetermined limit and no occupancyis determined in the units it services, flow meter and valve 962 may beactivated to shut off water to the entire branch line 956. Similarly, ifexcessive flow is sensed in branch 958 which services units 900B, 900D,and 900F, flow meter and valve 964 may be activated to shut off flowthrough branch line 958. Also, in the event that excessive flow isdetermined to occur in main line 954, flow meter and valve 960 may beactivated to shut off supply to the entire building 952.

While FIG. 16 has been described as a building 952 with multiple tenants900A-F, it is to be appreciated that this exemplary description may bescaled up or down without departing from the present invention. Forinstance, system 950 can be scaled down such that each “unit” 900A-Frepresents a specific water-using appliance or fixture within a singlehome. In this example, a unit may include a toilet, a dishwasher, asprinkler system, or any device that utilizes a water supply. Likewise,each main and branch line 954, 956 and 958 may represent variousplumbing branches within a home leading to each water-using appliance.Using this scaled down version of system 950, each water-consumingcomponent in a home may be protected to thereby provide a high degree ofclarity on what particular device is experiencing an over-flow conditionwhile allowing the other properly functioning systems to continue normaloperation. This component-level over-flow detection also provides theuser with a specific fault condition for a specific appliance or fixtureinstead of a whole-house fault which in some cases can result inincreased diagnostics and repair costs, and possible increased waterdamages.

The system 950 may also be scaled up to accommodate large buildings withmultiple units over multiple floors to provide a high degree of locationspecific over-flow detection. Likewise, this system 950 may be scaledlarger to provide for building to building level flow monitoring, andeven block to block levels of measurement and control depending on theenvironment of the system and its installation purpose.

While there have been shown what are presently considered to bepreferred embodiments of the present invention, it will be apparent tothose skilled in the art that various changes and modifications can bemade herein without departing from the scope and spirit of theinvention.

The invention claimed is:
 1. A device for interrupting a flow of fluidthrough a fluid conduit upon detection of a leak, comprising: leakdetectors configured to detect a fluid leak from a fluid conduit; aprimary valve in fluid communication with said fluid conduit and throughwhich fluid directed to a property flows; at least two unit valves influid communication with said fluid conduit, each unit valve associatedwith a unit of the property and through which fluid directed to theassociated unit flows; a controller in communication with said leakdetectors and said unit valves and configured to establish a geo-fencingboundary about said unit valves and said leak detectors; a means todetect any occupant of a plurality of occupants within said geo-fencingboundary in communication with said controller and configured to outputan occupied signal upon detection of an occupant within said geo-fencingboundary and output a vacant signal when no occupant is detected withinsaid geo-fencing boundary a timer means for delaying transitions fromsaid occupied signal to said vacant signal; and wherein upon detectionof said occupied signal said controller monitors for a home leak signalfrom said leak detectors and upon detection of said vacant signal saidcontroller monitors for an away leak signal from said leak detectors;wherein a unit valve of said at least two unit valves is closed whensaid home leak signal or said away leak signal indicates a leak in thecorresponding unit; and wherein said primary valve is closed when saidhome leak signal is detected and indicates a leak in at least two unitsand said primary valve is closed when said away leak signal is detectedand indicates a leak in at least two units.
 2. The device forinterrupting a flow of fluid through a fluid conduit upon detection of aleak of claim 1, wherein each of said leak detectors comprises: a firstsensor in thermal communication with said fluid within said fluidconduit and capable of sensing the ambient temperature of said fluid; asecond sensor in thermal communication with said fluid within said fluidconduit and responsive to a drive signal to elevate the temperature ofsaid second sensor to an elevated temperature; and a leak detectorcontroller in communication with said first sensor and said secondsensor configured to sense said ambient temperature from said firstsensor and generating said drive signal to drive said second sensor tosaid elevated temperature greater than said ambient temperature and togenerate a leak signal when said drive signal of said second sensorexceeds a leak point value.
 3. The device for interrupting a flow offluid through a fluid conduit upon the detection of a leak of claim 1,wherein each of said leak detectors comprises: a temperature sensor; aheating element located a distance downstream from said temperaturesensor, wherein heat energy created by said heating element propagatesupstream towards said temperature sensor; a leak detector controllerconnected to said temperature sensor and said heating element; whereinsaid temperature sensor senses said heat energy created by said heatingelement and said controller calculates a propagation time of said heatenergy from said heating element to said temperature sensor, saidpropagation time is a direct function of a fluid flow rate; and whereinsaid leak detector controller is configured to generate a leak signalwhen said fluid flow rate exceeds a leak point value.
 4. The device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak of claim 1, wherein each of said leak detectors comprises: afirst sensor in thermal communication with said fluid within said fluidconduit and capable of sensing an ambient temperature of said fluid; asecond sensor in thermal communication with said fluid and responsive toa drive signal to elevate a temperature of said second sensor; a meansfor generating said drive signal in communication with said secondsensor to drive said second sensor to an elevated temperature above saidambient temperature; and a means for detecting the flow of fluid throughsaid conduit.
 5. The device for interrupting a flow of fluid through afluid conduit upon the detection of a leak of claim 1, wherein each ofsaid leak detectors comprises: a first sensor in thermal communicationwith said fluid within said fluid conduit and capable of sensing anambient temperature of said fluid, wherein said first sensor includes afirst temperature sensing element; a second sensor in thermalcommunication with said fluid within said fluid conduit, wherein saidsecond sensor includes a second temperature sensing element and a heaterthermally coupled to said second temperature sensing element; anadjustable Wheatstone bridge circuit consisting of the first and secondtemperature sensing elements and having a first output and a secondoutput; a servo amplifier configured to drive the heater consisting of:a first input in electrical communication with the first output of thebridge circuit; a second input in electrical communication with thesecond output of the bridge circuit; and a power transistor having anoutput in electrical communication with the heater; an adjustablecomparator consisting of: an input connected to the output of the powertransistor; and an output; wherein the power transistor drives theheater in response to the difference in temperature between the firsttemperature sensing element and the second temperature sensing element;and wherein the adjustable comparator is configured to change state whenthe output of the power transistor exceeds a threshold; and wherein saidsecond sensor is positioned downstream from said first sensor.
 6. Adevice for interrupting a flow of fluid through a fluid conduit upon thedetection of a leak, comprising: leak detectors configured to detect aleak from a fluid conduit by monitoring a fluid flow rate of said fluidconduit; a primary valve in fluid communication with said fluid conduitand through which fluid to a property flows; a plurality of unit valvesin fluid communication with said fluid conduit, each unit valveassociated with a unit of the property and through which fluid directedto the associated unit flows; a controller configured to establish ageo-fencing boundary about said primary and unit valves and said leakdetectors and is in communication with said leak detectors and saidprimary and unit valves; a plurality of occupant sensors configured todetect a person within said geo-fencing boundary and output an occupiedsignal when a person is detected and output a vacant signal when noperson is not detected for a predetermined period of time, wherein eachsaid occupant sensor is in communication with said controller; whereinsaid controller is further configured to monitor said leak detector foran away fluid flow rate threshold upon detection of said vacant signaland output an away leak signal when said away fluid flow rate thresholdis met for a unit, to monitor said leak detector for a home fluid flowrate threshold upon detection of said occupied signal and output a homeleak signal when said home fluid flow rate threshold is met for a unit,and to close said primary valve upon detection of an away leak signalfor at least two units and close said primary valve upon detection ofsaid home leak signal for at least two units, and to close a unit valveof said plurality of unit valves upon detection of said home leak signalor said away leak signal for the corresponding unit.
 7. The device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak of claim 6, wherein each said occupant sensor comprises: aradio frequency identification tag; and a radio frequency identificationreader.
 8. The device for interrupting a flow of fluid through a fluidconduit upon the detection of a leak of claim 6, wherein each saidoccupant sensor comprises a motion sensor.
 9. The device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak of claim 6, wherein each said occupant sensor comprises aninfrared sensor.
 10. The device for interrupting a flow of fluid througha fluid conduit upon the detection of a leak of claim 6, wherein eachsaid occupant sensor comprises: a GPS enabled device; and a means todetermine a location of said GPS enabled device.
 11. A device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak, comprising: a controller configured to establish a geo-fenceboundary and configured to detect a home leak signal and an away leaksignal; a primary valve in fluid communication with a fluid conduit; amulti-unit property comprising a plurality of units, each unit having: avalve and flow meter in fluid communication with the fluid conduit; aportable electronic device having a global positioning satelliteposition detector capable of determining a position; a means forcommunicating said position to said controller; a means for comparingsaid position to said geo-fence boundary; a means for temporarilyoverriding the operation of said geo-fence boundary; and a means fordetecting an over flow condition and generating a fault signal inresponse thereto; wherein the valve of a unit of the plurality of unitscloses in response to a fault signal generated for the unit, and whereinthe primary valve closes when said home leak signal or said away leaksignal is detected and indicates a leak in at least two units of theplurality of units.
 12. The device for interrupting a flow of fluidthrough a fluid conduit upon the detection of a leak of claim 11,further comprising a means to detect a leak condition and generatingsaid fault signal in response thereto.
 13. The device for interrupting aflow of fluid through a fluid conduit upon the detection of a leak ofclaim 12, further comprising an occupant sensor.
 14. The device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak of claim 13, wherein said occupant sensor is a motion sensor.15. The device for interrupting a flow of fluid through a fluid conduitupon the detection of a leak of claim 13, wherein said occupant sensoris an infrared sensor.
 16. The device for interrupting a flow of fluidthrough a fluid conduit upon the detection of a leak of claim 13,wherein said occupant sensor is a radio frequency identification tag andreader.
 17. The device for interrupting a flow of fluid through a fluidconduit upon the detection of a leak of claim 13, wherein said occupantsensor is a bypass timer.
 18. The device for interrupting a flow offluid through a fluid conduit upon the detection of a leak of claim 13,wherein said means to detect a leak condition and generating said faultsignal in response thereto comprises: a first sensor in thermalcommunication with said fluid within said fluid conduit and capable ofsensing the ambient temperature of said fluid; a second sensor inthermal communication with said fluid within said fluid conduit andresponsive to a drive signal to elevate the temperature of said secondsensor to an elevated temperature; and a leak detector controller incommunication with said first sensor and said second sensor configuredto sense said ambient temperature from said first sensor and generatingsaid drive signal to drive said second sensor to said elevatedtemperature greater than said ambient temperature and to generate saidleak condition when said drive signal of said second sensor exceeds aleak point value.
 19. The device for interrupting a flow of fluidthrough a fluid conduit upon the detection of a leak of claim 13,wherein said means to detect a leak condition and generating said faultsignal in response thereto comprises: a temperature sensor; a heatingelement located a distance downstream from said temperature sensor,wherein heat energy created by said heating element propagates upstreamtowards said temperature sensor; a leak detector controller connected tosaid temperature sensor and said heating element; wherein saidtemperature sensor senses said heat energy created by said heatingelement and said controller calculates a propagation time of said heatenergy from said heating element to said temperature sensor, saidpropagation time is a direct function of a fluid flow rate; and whereinsaid leak detector controller is configured to generate a leak conditionwhen said fluid flow rate exceeds a leak point value.
 20. The device forinterrupting a flow of fluid through a fluid conduit upon the detectionof a leak of claim 13, wherein said means to detect a leak condition andgenerating said fault signal in response thereto comprises: a firstsensor in thermal communication with said fluid within said fluidconduit and capable of sensing an ambient temperature of said fluid; asecond sensor in thermal communication with said fluid and responsive toa drive signal to elevate a temperature of said second sensor; a meansfor generating said drive signal in communication with said secondsensor to drive said second sensor to an elevated temperature above saidambient temperature; and a means for detecting the flow of fluid throughsaid conduit.